Pakistani officials say a U.S. drone strike has killed at least four militants in the country's northwest tribal region.

The missiles hit a vehicle and a house Monday in North Waziristan tribal agency's Degan village, near the Afghan border.

Pakistani officials say those killed were from Turkmenistan.

Drone strikes resumed earlier this month after a drop-off in such attacks following the killing of 24 Pakistani troops in a NATO airstrike. That attack brought U.S.-Pakistan relations to a new low point.

Pakistan has condemned drone strikes as a violation of the country's sovereignty, but they are believed to be carried out with the help of Pakistani intelligence.

U.S. officials have never publicly acknowledged the missile strikes against militants in Pakistan's tribal areas, but have anonymously confirmed such attacks to various news outlets.